{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T09:09:01Z","timestamp":1789031341745,"version":"build-2803163510"},"reference-count":34,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T00:00:00Z","timestamp":1788912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22077053"],"award-info":[{"award-number":["22077053"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32271342"],"award-info":[{"award-number":["32271342"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["22077053"],"award-info":[{"award-number":["22077053"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"award":["32271342"],"award-info":[{"award-number":["32271342"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004826","name":"Beijing Natural Science Foundation","doi-asserted-by":"publisher","award":["2242022"],"award-info":[{"award-number":["2242022"]}],"id":[{"id":"10.13039\/501100004826","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Postgraduate Research & Practice Innovation Program of Jiangsu Province","award":["KYCX23_2568"],"award-info":[{"award-number":["KYCX23_2568"]}]},{"name":"Strategy Priority Research Program (Category C) of Chinese Academy of Sciences","award":["XDC0290302"],"award-info":[{"award-number":["XDC0290302"]}]},{"award":["XDC0290302"],"award-info":[{"award-number":["XDC0290302"]}],"id":[{"id":"https:\/\/ror.org\/034t30j35","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Congenital disorders of glycosylation (CDGs) are a growing group of inborn errors caused by gene defects in glycan biosynthesis pathways. Genetic testing of two patients from the same family harboring ALG1-related CDG (ALG1-CDG) revealed heterozygous variations in the c.1129 A&gt;C and c.1263+3 A&gt;T. Although most CDGs with abnormal N-glycosylation can be detected by transferrin screening, Western blotting of serum transferrin from the two siblings did not reveal significant glycosylation deficiency. In this study, the biochemical phenotype and pathological molecular basis of the CDGs in the siblings were further explored. Analysis of the patients\u2019 ALG1 cDNA indicated that the associated heterozygous variants were c.1129 A&gt;C (p.Met377Leu) and c.1188 T&gt;A (p.Cys396X). Single-molecule real-time (SMRT) sequencing indicated that the variant frequencies of M377L and C396X were 50% and 36%, respectively. In addition, glycoproteomics analysis suggested that the glycoforms of transferrin were altered in the patients and that glycosylation site occupancy was decreased. It was also confirmed that N-glycosylation was altered in the patients\u2019 serum transferrin. Conserved amino acid variants of yeast Alg1 were recombinantly overexpressed, purified and subjected to an in vitro quantitative activity assay. The results showed that these variants caused a decrease in enzymatic activity, suggesting pathogenicity.<\/jats:p>","DOI":"10.3390\/biom16091308","type":"journal-article","created":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T14:02:48Z","timestamp":1788962568000},"page":"1308","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Glycoproteomics and Functional Characterization of Novel Variants in Siblings with ALG1-CDG"],"prefix":"10.3390","volume":"16","author":[{"given":"Dongzhi","family":"Wei","sequence":"first","affiliation":[{"name":"State Key Laboratory of Biopharmaceutical Preparation and Delivery, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hui","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Biopharmaceutical Preparation and Delivery, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"College of Basic Medical Sciences, Dalian Medical University, Dalian 116044, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"}]},{"given":"Senlin","family":"Peng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Biopharmaceutical Preparation and Delivery, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Medical Genetics, School of Basic Medical Sciences, Peking University, Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"}]},{"given":"Ganglong","family":"Yang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Biopharmaceutical Preparation and Delivery, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"software","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2936-6896","authenticated-orcid":false,"given":"Weijie","family":"Dong","sequence":"additional","affiliation":[{"name":"College of Basic Medical Sciences, Dalian Medical University, Dalian 116044, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"supervision","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8575-5095","authenticated-orcid":false,"given":"Xiaodong","family":"Gao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Biopharmaceutical Preparation and Delivery, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ning","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Biopharmaceutical Preparation and Delivery, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"conceptualization","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1186\/s13023-023-02879-z","article-title":"Congenital disorders of glycosylation (CDG): State of the art in 2022","volume":"18","author":"Francisco","year":"2023","journal-title":"Orphanet J. 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